https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104713
Bug ID: 104713
Summary: gcc does not reject -march=i686 -fcf-protection
Product: gcc
Version: 11.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: bunk at stusta dot de
Target Milestone: ---
To support the Geode in OLPC, the toolchain definition of i686 does include
CMOV but it does not include multi-byte NOPs.
https://bugs.debian.org/1004894 is due to autodetection for -fcf-protection
that incorrectly succeeds with -march=i686.
The bug is likely in
https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/config/i386/i386-options.cc;h=805539364108eee07f5bda527acd6f39f3f7bf95;hb=HEAD#l2929
A similar problem in a different place was bug 84148.
Testcase:
$ touch test.c
$ gcc -m32 -march=i586 -fcf-protection -c test.c
cc1: error: ‘-fcf-protection’ is not compatible with this target
$ gcc -m32 -march=i686 -fcf-protection -c test.c
$
